i live in a small city, work in another, and often teach in a third, major city. the distance between the three is probably 70kms one way. home is seperated from the others by rural area. even though there is public transit, i prefer to commute by my own car, unless i don't have an option. (and i'm really uncomfortabble with that.)
we've already discussed edc in another thread. additionally, when i'm in the city, i try not to be far from my car. the scenarios i plan for, other than bugging in at home, are waiting out a storm or major accident and getting home. my edc will hopefully get me to my car from wherever i am, and i keep a backpack in the trunk that's designed to help me wait it out or get home. it's stocked with water, shelter, first aid, fire, heat, light, food, navigation, signalling, change of clothes, etc. my goal is for my son and i (my commuting partner) to be able to survive with it for at least 72 hrs.
he's got a pack in the trunk too, though less stocked (i.e. heavy), and we both dress in layers for the worst case weather in our area for the season. we also wear footwear suitable for hiking long distances. if i'm not wearing the appropriate clothes and/or footwear, they're in my pack in the trunk.